Effect of multicomponent exercise intervention on older adults with mild cognitive impairment based on HAPA-TPB theory (MIND-STEP): trial design and baseline data for a randomized controlled trial

Abstract Background Physical exercise has emerged as a promising non-pharmacological approach for improving cognitive and physical function in older adults with mild cognitive impairment (MCI). However, most existing interventions in nursing homes lack a strong theoretical foundation, standardized delivery, and evidence-based practice. This study aims to develop and evaluate a multicomponent exercise program grounded in the Health Action Process Approach-Theory of Planned Behavior theory (HAPA-TPB) to improve adherence and cognitive outcomes in older adults with MCI living in nursing homes. Methods This is a randomized, single-blind, parallel-group controlled trial conducted in nursing homes in Huzhou, China. A total of 156 older adults with MCI were randomly assigned to either a 12-week, group-based multicomponent exercise intervention or a control group receiving usual care. The intervention, theoretically grounded in an integrated HAPA-TPB framework, integrates aerobic, resistance, and mind–body training with structured behavioral change strategies designed to enhance motivation, adherence, and sustained engagement, including peer interaction. The primary outcome is cognitive function assessed by the Montreal Cognitive Assessment-Basic (MoCA-B). Secondary outcomes include physical performance, sleep quality, intrinsic capacity, frailty, social support, and intervention feasibility. Results A total of 1351 participants completed preliminary eligibility screening, of whom 156 were eligible and randomized (78 per group). The mean (SD) age was 69.19 years (SD = 8.97), and 69.23% of participants were female. Baseline characteristics were comparable across groups in terms of demographic, socioeconomic, and health status indicators. Baseline cognitive function, assessed using the MoCA-B, showed no significant between-group difference (intervention: mean = 17.29, SD = 2.32; control: mean = 16.74, SD = 2.19; F = 2.320, p = 0.130), indicating comparability prior to the intervention. Discussion This MIND-STEP study will provide high-quality evidence on the effectiveness and implementation of a theory-based, multicomponent exercise intervention for older adults with MCI in nursing homes. Findings will inform future intervention design and policy development to promote cognitive and functional health in institutionalized older populations. Trial registration Chinese Clinical Trial Registry ChiCTR2400088301. Registered on 15 August 2024.